1. Field
The present disclosure relates to a positive active material, a method of preparing the same, and a lithium battery including the positive active material, and more particularly, to a positive active material with improved initial efficiency and high-temperature stability.
2. Description of the Related Art
Lithium batteries, and in particular, lithium ion batteries (“LIBs”), have been used as a power source for portable, information technology (“IT”) devices due to high energy densities and ease of design. Recently, with use of lithium ion batteries as a power source for electric vehicles or power storage, research into materials for high-energy density or long-lifespan lithium ion batteries has been performed.
Much research has been performed into high-voltage positive active materials. However, high-voltage positive active materials usually have low initial efficiency and are not safe at high temperatures. Furthermore, high-voltage positive active materials in contact with an electrolyte may lead to side reactions on the surface of the positive active material, which is understood to cause self-discharge during storage at high-temperatures, and reduce high-temperature charging/discharging capacity.
Therefore, there still is a demand for a positive active material that provides improved initial efficiency and stability at high-temperatures while maintaining capacity during charging/discharging at high voltages and high temperatures.